Jul 29 2005
In order to avoid the dangers of multiple births, women having in vitro fertilisation may be limited to having just one embryo implanted at a time.
The Human Fertilisation and Embryology Authority (HFEA) announced yesterday that it is examining whether Britain should follow other nations that usually transfer one embryo.
Most couples want more embryos to be implanted to increase their chances of a pregnancy, and more than nine out of 10 In-Vitro Fertilization (IVF) cycles involves the transfer of two or even three embryos.
According to scientists the birth of twins or triplets leads to extra health risks for mothers and babies, as well as increased costs for families and the NHS.
The HFEA says it will work with other fertility and medical bodies to examine the issue from this autumn.
Angela McNab, the HFEA chief executive, says it is known that the biggest risk from fertility treatment is caused by multiple births.
She was speaking at a seminar in Manchester to clinicians and embryologists and said multiple births are more likely to be premature and the babies below normal birth weight, and this can have implications for the children's health and development.
It is also known that twins or triplets are much more likely to have cerebral palsy, to die around the time of birth or for there to be other complications during pregnancy, and multiple births place a substantial strain on the NHS.
Recent research by Prof Bill Ledger, of Sheffield University, showed that families conceiving triplets by IVF cost the NHS £32,354 in their first year of life, 10 times the cost of a single baby, because of the health complications suffered by the mother and children.
The HFEA wants to see the results of fertility treatment come closer to what occurs naturally, where women have healthy babies, one at a time.
From April this year women under 40 in England and Wales have been entitled to one IVF cycle paid for by the NHS.
However, because of shortages of eggs many couples are forced to pay for treatment.
In Belgium, couples are entitled to up to six free cycles of IVF treatment on the condition that in women under 36 only one embryo is transferred.
The Netherlands, Finland and Sweden have all moved towards single embryo transfer in recent years.
In Britain, 76.1 per cent of IVF cycles involved the transfer of two embryos and 14.8 per cent involved three in 2002-03 - the latest year for which figures are available.
Only 9.1 per cent of cycles involved a single embryo transfer.
In the same year 75.9 per cent of IVF births resulted in a single child, 23.6 per cent were twins and 0.5 per cent resulted in the birth of triplets.
The HFEA launched a policy last year limiting clinics to transferring two embryos to women under 40 and a maximum of three to those over 40.
A spokesman for the Royal College of Obstetricians and Gynaecologists agrees that this is the way for the future and is the only option in reducing the risk of multiple pregnancy.
He says there is now considerable experience from Finland, Sweden, Belgium and Holland where the introduction of single embryo transfer has been associated with a marked reduction in twin pregnancy rates but with no reduction in overall success rates.